What was found
NR 1 ENGINE, FIRE LOOP B FAULT ECAM MESSAGE IN FLIGHT. PERFORMED A BITE CHECK OF THE NR 1 AND 2 FDU IAW AMM 26-12-00-810-936. NR 1 FDIU FAULTED, LOOP B, NR 2 FDIU, NO FAULTS FOUND. STARTED, TROUBLESHOT OF PYLON FD LOOP IAW AMM 26-12, STEP 1, THRU 3B. TROUBLESHOT IAW TSM 26-12-00-810-936-A, FOUND LOOP DETECTOR 6WD1 LOW RESISTANCE BETWEEN PIN A OR C TRANSPONDER METAL CASING. REPLACED PYLON DETECTOR 6WD1 IAW AMM 26-12-16. TESTED OK. OK FOR SERVICE.